# # w wrint 写入（直接覆盖原内容）
# with open('./files/test.txt','w',encoding='utf-8') as f:
#     f.write('我是写入胡内容')




# # 练习 1.
# with open('./files/2file.txt','w',encoding='utf-8') as f:
#     s = '''2023-10-01 晴\n今天学习了python文件操作'''
#     f.write(s)


# # 2.
# date = input("请输入今天的日期：")
# weather = input("记录天气：")
# text = input("请编写日记：")
# # 今天心情有点美妙，我要中午睡觉，哈哈哈哈。
# with open('./files/3file.txt','w',encoding='utf-8') as f:
#     f.write(f"{date} {weather}\n")
#     f.write(f"{text.replace('，','\n\n')}")


# 3.
with open('./files/bil.txt','r+',encoding='utf-8') as f,open('./files/bil.txt.bak','w',encoding='utf-8') as f_bak:
    #备份
    res = f.read()
    f_bak.write(res)
    # 内容删除
    s = ""
    for line in res.split('\n'):
        #如果找不到返回-1
        if line.find('测试') == -1:
            s += line + '\n'
    # 回转指针
    f.seek(0)
    # 清空内容
    f.truncate()
    # 写入新内容
    f.write(s)

    